Power driven rotary files are well known. Typically these employ a number of elongated cradles which are horizontally suspended between and about the peripheries of a pair of spaced traveling devices which are driven so that the cradles are presented one by one before the operator who normally sits at a table or shelf at the front of the file. Some means of course for selecting the cradles one by one is necessary. These are generally essentially electrical in nature and are typically operated by a layout of buttons, one for each cradle, disposed at some location on the front of the file. Usually the files are quite wide and the operator must move bodily back and forth across the front of the file for access to different portions of a cradle. If the location of the selector controls is fixed, the operator, owing to the width of the cradle, often must move bodily sideways in order just to reach the controls so that a new cradle can be selected and then back again for access to the desired position of the new cradle. Even when the controls are mounted in some manner at some intermediate position between the ends of the file, the operator often must still reach to one side for them with one hand or the other. Furthermore, when the controls are mounted at some intermediate position, which is usually on the shelf itself at the center, they are often in the operator's way, requiring him to work over the controls and to move work papers each time access to the controls is necessary.
U.S. Pat. No. 2,928,706 discloses a movable set of selector controls for files of the nature concerned in the form of a telephonelike dial selector at the end of a flexible electrical cable, the dial being mounted in a loose housing free to be slid about by the operator on the shelf before the file. A somewhat similar approach, in the case of card selection apparatus, is shown in U.S. Pat. No. 2,922,424. However, in the latter instance, the movable controls, though movable along a fixed track, are both bulky and complicated. In the former instance the dial selector, though much less bulky. is relatively complex, costly and slow, and since it is loose on the shelf, can easily be knocked off. Hence, the primary object of the present invention is the provision of movable cradle selector controls for motorized rotary files which are simple, inexpensive, small in bulk, do not interfere with the operator, and cannot be knocked off the shelf.